notes/node_modules/duplexer2/README.md

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duplexer2 [![build status](https://travis-ci.org/deoxxa/duplexer2.png)](https://travis-ci.org/deoxxa/fork)
=========
Like duplexer (http://npm.im/duplexer) but using streams2.
Overview
--------
duplexer2 is a reimplementation of [duplexer](http://npm.im/duplexer) using the
readable-stream API which is standard in node as of v0.10. Everything largely
works the same.
Installation
------------
Available via [npm](http://npmjs.org/):
> $ npm install duplexer2
Or via git:
> $ git clone git://github.com/deoxxa/duplexer2.git node_modules/duplexer2
API
---
**duplexer2**
Creates a new `DuplexWrapper` object, which is the actual class that implements
most of the fun stuff. All that fun stuff is hidden. DON'T LOOK.
```javascript
duplexer2([options], writable, readable)
```
```javascript
var duplex = duplexer2(new stream.Writable(), new stream.Readable());
```
Arguments
* __options__ - an object specifying the regular `stream.Duplex` options, as
well as the properties described below.
* __writable__ - a writable stream
* __readable__ - a readable stream
Options
* __bubbleErrors__ - a boolean value that specifies whether to bubble errors
from the underlying readable/writable streams. Default is `true`.
Example
-------
Also see [example.js](https://github.com/deoxxa/duplexer2/blob/master/example.js).
Code:
```javascript
var stream = require("stream");
var duplexer2 = require("duplexer2");
var writable = new stream.Writable({objectMode: true}),
readable = new stream.Readable({objectMode: true});
writable._write = function _write(input, encoding, done) {
if (readable.push(input)) {
return done();
} else {
readable.once("drain", done);
}
};
readable._read = function _read(n) {
// no-op
};
// simulate the readable thing closing after a bit
writable.once("finish", function() {
setTimeout(function() {
readable.push(null);
}, 500);
});
var duplex = duplexer2(writable, readable);
duplex.on("data", function(e) {
console.log("got data", JSON.stringify(e));
});
duplex.on("finish", function() {
console.log("got finish event");
});
duplex.on("end", function() {
console.log("got end event");
});
duplex.write("oh, hi there", function() {
console.log("finished writing");
});
duplex.end(function() {
console.log("finished ending");
});
```
Output:
```
got data "oh, hi there"
finished writing
got finish event
finished ending
got end event
```
License
-------
3-clause BSD. A copy is included with the source.
Contact
-------
* GitHub ([deoxxa](http://github.com/deoxxa))
* Twitter ([@deoxxa](http://twitter.com/deoxxa))
* Email ([deoxxa@fknsrs.biz](mailto:deoxxa@fknsrs.biz))